The find, by a woman walking her dogs on the banks of the Fraser River in the Vancouver suburb of Richmond, rekindled speculation of a murder mystery, or airplane or boat accident behind the phenomenon.

Police said that the latest foot, in a small woman's New Balance running shoe, matched another found in May.

Neither was identified by police as a left, or right, foot.

Sergeant Kathrine Hansen of the Royal Canadian Mounted Police said: "The woman thought it was a leftover Halloween joke at first, then called us when she figured out it wasn't."